1. Field of the Invention
This invention relates to a yarn supply apparatus, particularly for textile machines, which can supply a yarn wound around a cheese to a needle under invariable tension by rotating disks so that the yarn can graze past the disks when weaving or knitting textiles using a weaving machine or a knitting machine.
2. Disclosure of Related Art
Generally, to produce textiles having uniform evenness and smoothness using a weaving machine or a knitting machine, a yarn should be supplied to a means of the subsequent process, particularly a needle knitting textiles under invariable tension and also different substances such as dust and the like should be prevented from adhering to the yarn.
A conventional yarn supply apparatus shown in FIG. 1 has an attachment part (508) to assemble it on the upper part of a knitting machine, and a rotary pully (500) over the holder body (50) and a yarn supply reel (501) under the holder body (50) which are constituent of said yarn supply apparatus are coaxially secured to the rotary shaft (503) together.
Said yarn supply reel (501) is embodied in the form of a cylindrical cage having a number of elongated metallic rods (501a) located between two flanges (505), (507), thereby the yarn passed in the order of a yarn guiding eyelet (100) and a disk (506) is wound around said metallic rods (501a) to form a plurality of loops of yarn windings. The yarn stored around said metallic rods (501a) of the yarn supply reel (501) is continuously let off from the lower side thereof to a let off guiding member (504), the first let off eyelet (504a) and the second let off eyelet (504b).
Said yarn which is let off to the lower side of the yarn supply reel (501) is let off without trembling since it is delivered to a needle of a textile knitting part (not shown) in condition of non-contact with the lower flange (507) of the yarn supply reel (501).
As another conventional art, the yarn supply apparatus described in Korea Patent Registration No.29468 which is the corresponding Korean Patent application of U.S. Pat. No. 4,793,565 has a storage drum having a drum shaft, a drum body, and a plurality of elongated yarn support elements distributed circumferentially around the drum shaft at a given radial distance therefrom and extending substantially in the direction of the drum shaft; each of the yarn support elements being in the form of a narrow yoke secured at both ends to the drum body and having, on a yarn supply side of the drum body, a first portion tapering radially inward toward the drum shaft to form a run-on incline for oncoming yarn and, adjoining this first portion, a second portion that at least in some segments is substantially straight and that forms a yarn support region for a plurality of loops of one yarn winding, wherein the first and second portions of all the yokes are, respectively, each located on common imaginary rotational bodies that are coaxial with the drum shaft; yarn delivery means for feeding yarn to the yarn supply side of the drum body; yarn run-off for removing yarn tangentially from a rim on a yarn run-off side of the drum body to a location positioned laterally of the drum shaft direction; a drive means coupled to the storage drum for attaining a relative rotation between the storage drum and the yarn delivery means and yarn run-off means; the drum body having the yarn supply side located toward one end of the drum shaft, a yarn run-off side toward the other end of the drum shaft including the rim which is a radially protruding, circular, continuous yarn run-off rim extending further axially from the yarn supply side than does the substantially straight second portion of the yakes, and means on the yarn run-off side for preventing accumulation on the yarn run-off side of fiber parts shed by the yarn, including means for defining a circumferential surface which is engaged by the yarn and extends, in the drum shaft direction, toward the yarn supply side from the run-off rim, and is radially inwardly inclined toward the drum shaft, the surface being coaxial with and coupled to the drum shaft and continuous in the circumferential direction, at least in regions located between adjacent yokes, at least part of the surface being, in the drum shaft direction, between the yarn supply side and the location to which the yarn is removed, the yokes entering the surface to form a substantially smooth transition zone therebetween; whereby the circumferential surface on the yarn run-off side of the storage drum is axially stripped continuously by yarn running off the yarn run-off rim to clear the drum of fiber parts shed by the yarn.
However, the yarn supply apparatus of the above invention has problems that magnets should be assembled in disks in order to invariably keep tension of a yarn using the frictional force occurring between disks attached by magnetic force and a yarn passing through the disks in the process of supplying a yarn to a storage drum and that a portion of yarn wears because disks are rotated by frictional force and thus the dust such as yarn ends is stacked on the surface of the yarn supply apparatus.
Further, it is a problem that disks of the above invention protrude toward one side of a holder body so that dust and the like adhere on the disks and thereby the yarn adhered different substances such as dust are supplied to a needle, thereby hindering the subsequent process.